Promession is an "environmentally friendly form of burial" in which human remains are disposed by way of freeze drying. It was invented by Swedish biologist Susanne Wiigh-Mäsak, who founded Promessa Organic AB in 1997.
Promession involves five steps:
- The body is frozen by immersion in liquid nitrogen, which makes it brittle.
- The frozen remains are shattered by vibration.
- The remains are then subjected to a vacuum so that the ice sublimes and the powder becomes dry, and weighs 50% to 70% less than the original body.
- Any metals (e.g., tooth amalgam, artificial hips, etc.) are removed, either with a magnetic process or sieving.
- The dry powder is placed in a biodegradable casket which is interred in the top layers of soil, where aerobic bacteria decompose the remains into humus, or compost, in as soon as 12 months.
Environmental advantages 
The advantages of Promession over cremation are that there are no polluting direct emissions to the atmosphere, whereas cremation usually uses fossil gas (methane, CH4) and releases carbon dioxide (CO2), oxides of nitrogen (NOx) and mercury vapour from dental fillings. Compared to standard burial, Promession does not release CH4 as the decomposition is aerobic, whereas in a deep grave, conditions are lacking in oxygen and aerobic decomposers would not survive. Traditional burial may contaminate the soil and groundwater with the liquids that are released from decomposition. Promessed remains are effectively recycled into soil.
The King of Sweden recognized Wiigh-Mäsak's business innovation with an award.
Current status 
Trials have been been performed on pigs — as early as 2004, AGA Gas developed a proof-of-concept. After years of R&D and successive improvements, Promessa is now at a point where manufacturing a facility to enable promession for humans has become feasible.
Some independent attempts to reproduce Promessa's early results have so far been unsuccessful. By means of explanation, the original innovators point to a lack of skills concerning cryogenic freezing and vibration technology. The BBC has shown a proof of concept to work with relatively simple means.
A third party has to enter into an agreement with Promessa to order the equipment needed for promession. Until this happens, no facility exists with which to take care of people whose last will stated promession.
International expansion 
Wiigh-Mäsak had received expressions of interest from more than 60 countries, including Vietnam, the United Kingdom, South Africa, the Netherlands, Canada, and the United States. In South Korea, the technology was expressly legalized and embraced by the church.
Public opinion 
Opinion polls in Sweden show that people prefer promession. The most recent is introduced in Ny Teknik. In a popularity contest among about 70 innovation companies in Sweden, Promessa has emerged as the most popular.
- McNally, Patrick (30 September 2008). "Promession: A Return to the Living Soil". Daily Undertaker. Retrieved 26 September 2012.
- Holst, Karen (13 April 2011). "Swedish green-burial firm to turn frozen corpses in compost". Retrieved 26 September 2012.
- Stansfield, Jem (16 April 2013). "Bang Goes The Theory". Retrieved 8 May 2013.
See also